1. Field of the Invention
This invention relates to recording media having a recordable region therein that is protected from surface damage, and more particularly to recording media wherein the protection afforded does not require the user to add any packaging or apparatus to, or remove packaging or apparatus from, the recording medium in order for that protected recording medium to be recorded upon, read, transported or stored.
2. Background Information
Recording media come in a variety of shapes. Well-known examples in the art include the compact disc (CD) and the vinyl or plastic stereo record (LP). The medium of such CDs and LPs presents a portion of at least one face of a flat circular disc (hereinafter referred to as the recordable region) to be recorded upon and subsequently read (by a laser in the case of CDs or a stylus needle in the case of LPs). Recording onto the recordable region of the medium is done by techniques that produce a microstructure within the medium (pits in the case of CDs; grooves in the case of LPs). This recordable region, and any microstructure recorded upon it, are and remain vulnerable to surface damage throughout the life of the medium. Any material that would adhere to, scratch or otherwise distort the face of, or any microstructure recorded upon the face of, the recordable region would also reduce the recordability and/or readability of that recording medium.
During handling of the medium, users may touch the exposed recordable region and leave oily fingerprints and grime thereon. Also, users may cause the recordable region to be placed upon flat surfaces that bear a quantity of dust, dirt, and the like that can easily attach to the recordable region via static electrical attraction, or by becoming embedded in the oily residue of a fingerprint. Once attached, the dust and dirt may scratch, mar or otherwise distort the blank or pre-recorded recordable region, especially when placed against a hard rotating surface such as occurs when the media are stacked upon each other in an apparatus which rotates when reading the medium. Due to the cost of recording media (whether sold as blank or pre-recorded), effort has been made to develop means for protecting such recording media from common types of accidental damage incurred by improper handling, stacking, transport and storage.
Well known devices for protecting recording media during long-term storage are sleeves and boxes. See, e.g., U.S. Pat. No. 4,736,840 issued Apr. 12, 1988 to Deigimeier describing a protective circular envelope into which the CD may be inserted for storage but which must be removed prior to reading; U.S. Pat. No. 5,299,186 issued Mar. 29, 1994 to Tsurushima describes a CD protective cover that is installed about the CD for storage but which likewise must be removed for reading.
Stacking devices for separating stacked recording media during reading are also known to the art. See, e.g., U.S. Pat. No. 4,589,104 issued May 13, 1986 to Brockley that describes a spacer apparatus into which LPs may be loaded; and U.S. Pat. No. 4,316,281 issued Feb. 16, 1982 to Prusak, describes a spacer for video discs which are stacked one above the other.
Recognizing the need for a protective device that can remain essentially a permanent part of a particular medium for protective purposes, while also allowing the reading of that medium with that protective device in place, on Dec. 20, 1996, the present inventor filed U.S. patent application Ser. No. 08/771,011 that describes a flexible, annular protector ring having an annular spacer extending therefrom, that protector ring then being snapped around the edge of a recording disc so as to provide a spacer that will maintain the lower-side recordable region thereof out of contact with a surface upon which the medium may be placed. An annular groove disposed on the upper surface of that protector ring in a corresponding position can be engaged by a second such disc-protector ring combination, thereby permitting two or more such disc-protector ring combinations to be stacked one upon the other so as to preclude relative sliding motion therebetween.
It has also occurred to the present inventor, however, that there remains a need for a recording medium that is protected but which does not require the user to add a protective apparatus to such medium, move the medium into a separate protecting apparatus, or to add a protecting apparatus to a reader of the medium. The present specification and drawings disclose such a protected recording medium, specifically by adopting the aforesaid annular spacer not as a part of an added protective apparatus but rather as an integral part of the recording disc itself.